Editor's Note: This article was orginally published Sept. 1, 2018. Some of the information may no longer be relevant, so please use it at your discretion.
Undercar service, diagnostics and repair have become more complex with advancements in vehicle weight reduction. Technicians will need to be aware of industry standard equipment and best-practices in order to correctly perform these services. Understanding how to build this equipment into a shop’s business model could also provide a new revenue stream for shop owners. Tire, wheel and brake service as well as noise vibration and harshness (NVH) diagnostics are great starting points when considering an upgrade to your current undercar service offerings.
If you haven’t already noticed, every vehicle manufacturer is working to make their vehicles lighter in order to improve overall fuel economy and emissions. With the move towards “light-weighting,” every possible method for weight reduction is in play. The effect this has had on undercar service is that every vibration is now amplified through the lighter weight components that have an inherent ability to carry vibration frequencies from the road to the driver.
Today’s undercar service technician has to be aware of all areas of noise, vibration and harshness (NVH). Jobs such as tire replacement, wheel balancing, alignment, and rotor machining have all become complex due to vibration concerns and require technicians and shop owners to raise their level of awareness, understanding, and tooling to stay current. Additionally, vibrations that can’t be easily pinpointed will require the technician to have a fundamental understanding of NVH diagnostics.
Tire mounting
In an effort to make wheel assemblies lighter many manufacturers have moved to plastic cladded wheels to decrease overall wheel assembly weight. Wheel designs have also added expense with some European varieties priced at over $2,000. What this means for you is that the old center clamp tire machine is ready for the scrap pile or a sale or donation to a restoration shop. It also means that a job that was relatively straightforward in the past, now comes with additional complications. How many scratched or damaged Audi wheels can your shop support? I think you get the idea.
In order to perform tire mounting, shops now have several choices:
- Send tire work to the tire shop down the street
- Be the shop down the street
While new, non-contact tire machines may appear expensive, forward thinking shops have realized that this new equipment can help to establish them as a go-to for tire replacement and ultimately turn tire service into a profit center for their business. As an example, the Hunter Revolution tire changer is claimed to be a fully-automatic tire machine designed for its ease of use and built in efficiency. Once the technician sets the first tire up on the machine, a task that requires no lifting, the technician can walk away from the subsequent tire dismounts and let the machine do the work.
While this is happening, the technician can spend his or her time at the wheel balancer. Hunter.com claims this machine can save the technician 25 percent or more time as compared to traditional tire machines. Additionally, the leverless design of this machine allows for mounting and dismounting without tool contact with the wheel, preventing costly wheel repairs.
Wheel balancing
Growing up in auto shops we were all familiar with the concepts of static and dynamic balancing. However, balancing does not always ensure that a vehicle’s tire will roll smoothly over the road. With the vibration concerns on today’s vehicles, NVH from the force, the road applies to a tire needs to be examined. This can only be accomplished by applying a force to the tire during the overall wheel balancing process.
This process will inform the technician as to the overall ability of the tire to roll smoothly over the road and ensure the car will ride like it was intended to from the factory. To perform this function, a shop will need to possess a balancer with a road force drum. In many instances, the road force process will instruct the technician to reposition the tire on the wheel assembly, provide suggested locations for weight placement to compensate for imperfect tires, and in some cases, may inform the technician that a tire is severely out of spec and will need replacement. If your shop is performing an extensive amount of tire and wheel service, this machine may soon become a necessity if it has not already.
Alignment
Wheel alignment has also evolved with the light-weighting trend as new wheel assemblies require equipment that cannot make contact with the rim. In addition to the wheel alignments we are all familiar with, Hunter has patented a second alignment; Safety System Alignment. This addition to Hunters alignment software was designed to address the need for additional procedures following a wheel alignment including calibration of steering angle sensors, camera based lane detection systems, radar based object detection and other future technologies. Utilizing their patented CodeLink technology previously utilized to reset steering angle sensors and a set of proprietary aids and targets, Hunter has created the ability to perform advanced functions on Ford, Lincoln, Chrysler, Dodge, Jeep, Nissan and Infiniti vehicles with more in development. While not directly an alignment function, these tasks are becoming a part of the job for many vehicles.
Brake service
The days of the off-car brake lathe are behind us. In order to address vibration concerns caused by excessive rotor runout, the stacked tolerances of the hub and rotor have to be taken into consideration. This has brought companies such as Pro-Cut International to the forefront of brake service within the dealership arena, and they are starting to make their way into independent shops. The on-car brake lathe has evolved drastically from the early versions we all remember. Set-up and use is very simple and will allow a technician to cut four rotors in approximately 20 minutes or less.
Consider the math: If you were to perform a brake service and are charging a customer for a rotor, a large part of the money paid to you by the customer will be going to the parts warehouse and not to your bottom line. On-car machining offers a way of offering a brake service that is potentially more profitable than replacing rotors. The knock on the on-car machining process is that many rotors are already too thin to machine. While this can at times be true, the on car-process is also suggested when installing new rotors on a vehicle to ensure machined surface that will reduce the frequency of vibration comeback complaints after brake service.
NVH diagnostics
Often times a vibration cannot be easily located. You may be familiar with the “Chassis Ear” system that has been around for decades. Perhaps you remember the reed tachometer or the EVA? This equipment was taught for quite some time by the domestic OE manufacturers and oftentimes the independent shops were on the outside looking in when it came to this type of diagnostics. Additionally, the technician had to know the science behind matching a vibration frequency to a given system which provided a steep learning curve especially without access to some of the proprietary curriculum.
Recently, vibration software and hardware that interfaces with PC based oscilloscopes has been introduced as a factory tool by OE’s such as General Motors. PICO Diagnostics now offers a scope diagnostic solution that is available to the public for purchase. This hardware and software works with your existing four-channel PICO scope model 4425 and contains a microphone and accelerometer for monitoring noise and vibration levels and frequencies.
Advanced kits are also available and contain additional microphones and accelerometers. The beauty of this system is the diagnostic software helps the technician to identify the source of the vibration without a tremendous amount of experience and or prior knowledge of NVH diagnostics. According to Pico, the NVH kit can be used to diagnose cabin vibrations at speed, engine vibrations throughout the entire RPM range, clutch judder or vibration, transmission and bearing whine, transfer case noise, brake judder and steering vibrations. If you are a Pico 4425 owner, the NVH add-on kit starts at around $1,700 ,which includes the basic kit to get you started with diagnosing difficult vibration and noise concerns.
If you have ever encountered a driveline vibration caused by a an out-of-balance driveshaft, you may have had to pull the driveshaft and send it to a driveshaft shop to have it balanced or in some cases charge your customer a small fortune to replace it. Pico has a solution for this type of diagnostics and repair in the form of an optional NVH kit add on in the form of an optical sensor. In this kit the optical sensor is attached to a robust magnet that will help to keep the sensor in place while diagnosing a driveshaft vibration.
A technician can then diagnose and balance the driveshaft in place and view before and after graphs of the optical signal. This is considerably cheaper and more cost effective in many cases, than replacing or sending out a driveshaft for balancing. This kit is available starting around $400.
Certifications
The learning curve in our industry for both seasoned and new technicians is immense. Fortunately training is available and in the case of some of the pieces of equipment we have covered here, certifications are available as well. For example, Hunter.com features a variety of training options including e-learning and videos for those getting started with Hunter’s equipment. For those who prefer a live classroom environment, Hunter offers certification classes across the country in alignment and road force balancing. High School and College automotive programs can now offer certifications on Hunter equipment usage providing a recognizable credential.
Meaningful certification has become a topic that has not gone unnoticed by industry. The National Coalition of Certification Centers, known as “NC3,” has established partnerships with Snap-On, Pro-Cut International and Starrett to offer a variety of certifications for the automotive sector. These certifications include Precision measurement, Torque, multimeter, diagnostics, wheel service and alignment and master rotor machining. These certifications are available through secondary and post-secondary NC3 affiliate schools which offer the certification as either a part of a full-time program or through continuing education events for the local automotive community. In order to gain certification the student must participate in the course and demonstrate an understanding and competency in using the equipment and performing related tasks. For more information on how to gain these certifications please visit www.nc3.net for a list of member schools.
Training on Pico scopes and NVH are not as readily available. However, picoauto.com provides a wealth of information and resources for the dedicated learner including some fantastic case study videos of the NVH product in use.
As with any new technology, be prepared to spend some time doing your homework. Be informed, get training and gain the knowledge you need to perform these services while adding a new revenue stream to your business.
